69

I know questions on the "hot" tab of a site homepage are based on some sort of views/velocity criteria, but does anyone know the actual algorithm used?

Background: I was considering a feature-request about the "hot" tab, but I don't have enough information to speak about it intelligently.

2
  • 2
    What hot questions? There are two kinds and for all we know they may share the same hotness formula or have two different formulae. One is the "hot tab" of each site, the other is the "pan-SE hot questions tab" in the "StackExchange" popup in the top-left of every page (which doesn't seem to have a URL but rather is only accessible by JavaScript). Commented Dec 8, 2011 at 16:06
  • 4
    This question referred to the 'hot' tab on Stack Exchange sites. This question was asked 2-1/2 years ago in July '09, when there was no pan-SE functionality. And, no, I don't know if they use the same algorithm or not. Commented Dec 8, 2011 at 16:28

1 Answer 1

48

What formula should be used to determine "hot" questions?

Based on my analysis of the above and the comments so far, here's the second version of what I have implemented so far. This might suck. I don't know:

(log(Qviews)*4) + ((Qanswers * Qscore)/5) + sum(Ascores)
--------------------------------------------------------
((QageInHours+1) - ((QageInHours - Qupdated)/2)) ^ 1.5

Note that I do not weight an accepted answer very heavily. This is intentional, as I feel accepted answers are a fine social contract, but not necessarily a good data point for question or answer quality.

Keep in mind that this is not the formula used to determine the Hot Network Questions list (including the one on the homepage sidebar); see: How do the “arbitrary hotness points” work on the new Stack Exchange home page?

5
  • 12
    Could you change the log to log10 (logarithm to the base 10) or the equivalent in the language you've implemented it in? That will decrease the weighting given to question views by a factor of ~2.3 Right now it's heavily skewed towards more views than quality (votes) Commented Aug 18, 2011 at 16:42
  • Does this cover both the per-site hot list and the pan-SE hot list? the latter seems to take into account how young or small a site is, at least during beta. Commented Dec 8, 2011 at 16:08
  • 2
    I don't quite follow the quoitient. Doesn't that penalise recently updated questions? Or is that the point? Commented Jan 18, 2012 at 18:36
  • How would all of that criteria, ie views, score, updated, differ from the activity sort? How is sorting on activity different from sorting on hot... Is a "hot" question one that simply has a lot of activity over a short amount of time?
    – reectrix
    Commented Feb 14, 2014 at 0:15
  • 2
    Is there any way to make a query in order to get the hot questions in the data explorer (data.stackexchange.com)?
    – leno
    Commented Mar 12, 2015 at 14:58

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .